(A) shows the most common running trace generated when the inner ring rotates under a radial load only.
(E) through (H) show different running traces that result in a shortened life due to their adverse effect on bearings.
(A)
Inner ring rotation
Radial load
(B)
Outer ring rotation
Radial load
(C)
Inner ring or outer ring rotation
Axial load in one direction
(D)
Inner ring rotation
Radial and axial loads
(E)
Inner ring rotation
Axial load and misalignment
(F)
Inner ring rotation
Moment load (Misalignment)
(G)
Inner ring rotation
Housing bore is oval
(H)
Inner ring rotation
No radial internal clearance
(Negative operating clearance)
Source: NSK